Generation of Ester Plasticizers for High Temperature Ethylene - PowerPoint PPT Presentation

Development of New Generation of Ester Plasticizers for High Temperature Ethylene Acrylic Elastomers 1

Agenda • Background on EAM elastomers • Plasticizer for high-temperature AEM applications • Goal of the project • Overview of the experimental plan • Results and discussion • Conclusions • Acknowledgements 2

Background on AEM Elastomers • AEM are used in applications requiring continual service up to 175°C and intermittent exposure to extremely high temperatures of up to 200 °C • Lower cost alternatives to FKM and FVQM • Exhibit improved high temperature resistance over HNBR and ECO • There are two well known types: – ACM ( A crylic C o- M onomer) – AEM ( A crylic- E thylene M onomer) 3

Background on AEM Elastomers • Conventional CB and Silica fillers provide stiffness in AEM compounds but – Accelerate oxidative degradation – Reduce thermal stability • DuPont™ developed novel melt -blending technology which allowed reinforcement of AEM with a dispersion of grafted PA6 droplets • DuPont™ VMX 5000 elastomers are based on amine cure system • Result is a strong, heat-resistant elastomer compound with good heat-aging and compression set properties • Enhanced performance is due to – Extensive AEM-PA6 grafting – Absence of filler-filler contacts – Beneficial modification of oxidation profile under diffusion-limited conditions 4

Plasticizer for high-temperature AEM applications • Highly polar AEM elastomers require higher-polarity ester plasticizers to assure optimal compatibility • Due to the high post-cure and application temperature requirements few plasticizer have found utility in demanding AEM applications • Polar monomeric plasticizer have good low temperature properties but suffer from higher weight losses during high temperature aging • Polar high MW plasticizer have good permanence but lack optimal low temperature flexibility 5

Goal of the Project • To develop new generation of high-performance ester modifiers and help expand modifier options for the acrylic elastomer market. 6

Experimental Plan – Part I SAMPLES USED IN THIS STUDY 7

Testing 8

Original Properties – Part I TegMeR No 812 RX-14434 RX-14565 RX-14562 plasticizer Stress @ 100% Elongation, MPa 2.1 2.0 2.4 2.2 3.0 Stress @ 200% Elongation, MPa 5.6 6.2 7.1 6.6 9.1 Stress @ 300% Elongation, MPa 10.3 11.9 12.6 12.1 15.1 Tensile Ultimate, MPa 13.8 15.6 14.6 14.6 16.2 Elongation @ Break, % 382 367 348 359 318 60 60 63 58 65 Hardness Duro A, pts. 1.078 1.078 1.078 1.078 1.079 Specific Gravity 9

Heat Aging – Weight Change, Part I Weight Change, % (Normalized) TegMer 812 RX-14434 RX-14565 RX-14562 0.4 • Neat AEM polymer exhibited 0.2 some weight loss so all of the 0 data were normalized. -0.2 -0.4 • Normalized data helped -0.6 -0.8 elucidate performance -1 differentiation between the 4 -1.2 samples used in this study -1.4 -1.6 2 wk @ 190 C 3 wk @ 190 C 4 wk @ 190 C 10

Heat Aging – Volume Change, Part I Volume Change, % (Normalized) TegMeR 812 RX-14434 RX-14565 RX-14562 • The compounds showing a 1 weight or volume “gain” are at low enough levels as to be 0.5 considered equivalent with the control compound, 0 effectively losing no weight or volume due to plasticizer loss -0.5 -1 -1.5 2 wk @ 190 C 3 wk @ 190 C 4 wk @ 190 C 11

Heat Aging – Changes in Elongation, Part I Elongation Change, % (Normalized) TegMer 812 RX-14434 RX-14565 RX-14562 5 0 -5 -10 -15 -20 2 wk @ 190 C 3 wk @ 190 C 4 wk @ 190 C 12

Heat Aging – Changes in Tensile Properties, Part I M100 Change, % (Normalized) 80 60 40 20 0 TegMer 812 RX-14434 RX-14565 RX-14562 2 wk @ 190 C 3 wk @ 190 C 4 wk @ 190 C 13

Heat Aging – Compression Set, Part I Compression Set, % 25 23.4 22.4 20 16.9 15.8 15.8 15 14.5 14.0 14.0 13.3 12.9 13.0 12.0 11.2 10.2 10.8 10 5 0 TegMeR 812 RX-14434 RX-14565 RX-14562 None Original 2 wk @ 190 C 4 wk @ 190 C 70 hrs at 150°C, under constant deformation 14

Original Tg, Part I Original Tg, °C TegMeR 812 RX-14434 RX-14565 RX-14562 -32 • As expected, TegMeR 812 is -33 most efficient at lowering Tg -34 compared to experimental -34.58 -35 polymeric materials -35.64 -35.68 -36 • All provide good starting Tg -37 -38 Ramping -100 to 70 C @ 20 C/min -38.46 -39 15

Heat Aging – Effect on Low Temperature, Part I Tg, before and after aging, °C TegMeR 812 RX-14434 RX-14565 RX-14562 None -28 • TegMeR 812, while starting -30 with the lowest Tg, loses the -32 most performance after aging -34 • RX-14562 retains the best -36 performance after aging -38 -40 Original 2 wk @ 190 C 3 wk @ 190 C 4 wk @ 190 C 16

Experimental Plan – Part II • Based on results from Part I, the formula was adjusted to increase plasticizer level • RX-14562, as the best performing material in Part I, is used as a control SAMPLES USED IN THIS STUDY 17

Original Properties – Part II No RX-14562 RX-14600 RX-14601 RX-14602 RX-14603 Plasticizer Stress @ 100% Elongation, MPa 2.6 2.7 3.1 2.8 2.7 4.4 Stress @ 200% Elongation, MPa 7.6 7.5 8.5 7.8 7.5 12.4 Stress @ 300% Elongation, MPa 12.8 13.2 --- 13.2 12.5 --- Tensile Ultimate, MPa 13.0 14.2 13.3 13.9 13.1 16.9 Elongation @ Break, % 305 320 293 316 308 275 Hardness Duro A, pts. 59 58 59 59 57 64 Specific Gravity 1.081 1.082 1.086 1.086 1.085 1.084 18

Heat Aging – Weight Change, Part II Weight Change (Normalized), % RX-14562 RX-14600 RX-14601 RX-14602 RX-14603 0 • Neat AEM polymer exhibited -0.5 some weight loss so all of the data were normalized. -1 2 wk @ 190 C -1.5 • Normalized data helped 3 wk @ 190 C 4 wk @ 190 C -2 elucidate performance differentiation between the 5 -2.5 samples used in this study -3 -3.5 19

Heat Aging – Changes in Elongation, Part II • All plasticizers show good behavior with elongation loss compared to non-plasticized control Elongation Change, % • RX-14562 and RX-14600 No RX-14562 RX-14600 RX-14601 RX-14602 RX-14603 Plasticizer show best retention of 0 -10 -20 elongation after aging -30 -40 -50 -60 -70 2 wk @ 190 C 3 wk @ 190 C 4 wk @ 190 C 20

Heat Aging – Changes in Tensile Properties, Part II • All plasticizers show good behavior with tensile strength loss compared to non- plasticized control Tensile Change, % • RX-14562, RX-14600, and No RX-14562 RX-14600 RX-14601 RX-14602 RX-14603 Plasticizer RX-14602 show best 0 -10 retention of tensile strength -20 -30 after aging -40 -50 -60 -70 2 wk @ 190 C 3 wk @ 190 C 4 wk @ 190 C 21

Heat Aging – Compression Set, Part II Compression Set 30 • Decrease in compression set 25 after aging in most cases 20 likely due to increased cross- Originals linking during aging 15 2 week aged • Increase in set after aging 4 week aged 10 likely due to degradation • RX-14602 overall best initial 5 compression set and 0 RX-14562 RX-14600 RX-14601 RX-14602 RX-14603 No Plasticizer retention after aging 70 hrs at 150°C, under constant deformation 22

Heat Aging – Effect on Low Temperature, Part II Tg by DSC, C RX-14562 RX-14600 RX-14601 RX-14602 RX-14603 -25 -27 • All plasticizers have excellent -29 initial low temperature -31 properties -33 • RX-14562 and RX-14602 -35 offer best retention of low -37 temperature properties after -39 heat aging -41 -43 Original 2 wk @ 190 C 3 wk @ 190 C 4 wk @ 190 C 23

Conclusions • Plasticizers tested here offer better performance than others in different aspects • Overall, RX-14562, RX-14600, and RX-14601 offer best maintenance of properties after extreme heat aging • Adjusting molecular weight and chemistries of polymeric materials can optimize properties according to application requirements 24